1. Field of the Invention
The present invention is an improvement of the invention set forth in commonly assigned application Ser. No. 528,711, filed May 24, 1990 now U.S. Pat. No. 5,005,883, issued Apr. 9, 1991 and relates to a improved device for indicating that an attempt has been made to tamper with a locking or security seal. More particularly, the present invention relates to an improved device for visually indicating that someone has tampered with or attempted to defeat a locking seal, security seal, or such as intermodal seal, on an ocean container, truck trailer, freight car, equipment cabinet, switch or other item which is intended to be, and to remain, secure.
2. Prior Art
Locking or security seals are used to nominally prevent tampering with, pilferage from, and unauthorized entry to or operation of various items. Such seals are also intended to provide an indication that an unauthorized attempt, successful or otherwise, has been made to enter or operate an item by tampering with or defeating the seal.
The doors of ocean containers, truck trailers, freight cars and equipment cabinets, as well as items such as railway switches and high-voltage switches are often secured with a locking, security or intermodal seal.
Typical seals include a metal male member, which may be a headed rigid bolt, or a flexible cable with a head at one end and a solid tip on the other end, and a metal female member or lock body for receiving the unheaded end of the bolt or the tip of the cable in a passageway thereof. Once the bolt end or tip end is inserted into the passageway, it is retained and restrained therein by appropriate facilities. These facilities may include a circumferential groove near the end of the bolt or tip and a circumferential groove in the wall of the passageway. A locking ring, C-ring or spring ring within the passageway surrounds the bolt or tip end and partially occupies the groove in the bolt or tip as well as the groove in the passageway to interfere with, and prevent, removal of the bolt or cable from the lock body. Other facilities for preventing removal of the bolt from the lock body may include spring-loaded fingers extending into the passageway and engaging notches in the bolt or tip.
Typical locking or security seals are shown and described in the following U.S. Pat. Nos., all but the last being commonly assigned with the present invention: 3,980,337; 4,152,909; 4,193,276; 4,326,740; 4,802,700; and 4,280,726.
To secure a door or other item, the bolt or cable may be inserted through an aperture in a latch, staple, hasp or other locking member in such a way as to interfere with opening, unlocking or operational movement thereof. Thereafter, the bolt or tip is inserted into and retained in the lock body as described above. A padlock or other locking device may be used in conjunction with the locking seal.
A locking or security seal will usually prevent opening of a door or other item when an interloper attempting same is an unsophisticated interloper, such as a vandal, casual thief or other person who does not possess a bolt cutter or other device for cutting the bolt or cable and/or breaking or removing the locking device, if one is used. However, sophisticated interlopers, such as professional thieves and others who possess appropriate tools like bolt cutters, may gain entry simply by cutting the bolt or cable of the seal (and the locking device where one is used). At times the sophisticated interloper may "reassemble" the cut seal by repositioning its now non-integral parts in such a way as to make it appear that defeat thereof and unauthorized entry or operation have not occurred. Another sophisticated approach may involve gross disintegration of one or more parts of the seal followed by replacement thereof with counterfeit parts associated together to mimic an integral, untampered seal.
The sophisticated interloper may also attempt to defeat the locking seal by inserting a shim or the like into the passageway between the end of the bolt or tip and the lock body to remove the ring or the fingers, therewithin from one of the circumferential grooves or notches, thus permitting removal or the bolt or tip end from the lock body. Following unauthorized entry, the locking seal may be reassembled to hide the fact of its defeat.
Thus, a locking or security seal is a physical deterrent, nominal or real, to unauthorized entry or operation in the same manner as a lock. It also serves as a psychological deterrent: interlopers may eschew attempting unauthorized entry which they known will be detected through later visual observation of the breaking of, or tampering-indicating marks on the metal parts of, the seal.
As noted, however, the seal may not successfully deter, physically, psychologically or otherwise, the professional thief or other sophisticated interloper who has the capacity to defeat the seal and to gain unauthorized entry or effect unauthorized operation. Where defeat of the seal is achieved by cutting or other gross disintegration thereof, or where a shim or similar device has been used, a clear indication of tampering is given, unless a successful apparent or actual reassembly has been effected with the original seal's elements or with counterfeits thereof.
It is usually desirable to detect unsuccessful attempts to tamper with or defeat a locking or security seal. For example, if there occur numerous or repeated attempts to gain unauthorized entry or to effect unauthorized operations at a specific location, detection of these attempts permits security or surveillance in such locations to be increased or improved so that the interlopers may be apprehended before they achieve their goal.
It is also desirable to detect successful attempts to tamper with or defeat a seal. Those successful attempts that are not accompanied by apparent or actual reassembly of the seal (or of counterfeit portions thereof), are easily visually detectable by observation of the non-integral seal.
Successful attempts at seal defeat followed by reassembly of the original seal (or its counterfeit) and failure to detect such reassembly are insidious. A theft following defeat of the seal may go undetected for some time, which may prevent identification of the location of the theft and render difficult apprehension of the perpetrators. Even more troublesome is the undetected placement of contraband, such as illicit narcotics, in an otherwise proper shipment of cargo. Moreover, undetected and unauthorized operation of an item following defeat of the seal may lead to untoward events caused by incorrect assumptions concerning the condition of the affected item. For example, an undetected change in the condition of an electrical or railway switch can lead to a catastrophic event.
Due to an unsuccessful attempt to defeat the seal or a successful attempt followed by reassembly of the seal (or its counterfeit), the metal lock body or the metal bolt or cable may bear marks, gouges or nicks giving visual evidence of the attempt. However, such marks may not be easily detected or may be overlooked. Also, the use of non-abrading or protective materials, such as rags or rubber sheets, in conjunction with grasping or holding tools used to defeat the seal may obviate or ameliorate such marks. Further, replacement and apparent reassembly of a defeated seal via the use of umarked counterfeit parts may go undetected.
An object of the invention of commonly assigned application Ser. No. 528,711, filed May 24, 1990 now U.S. Pat. No. 5,005,883, issued Apr. 9, 1991 is the provision of a device which will provide a visual indication of an attempt, successful or unsuccessful, to defeat a locking or security seal. The device of that invention provides this indication regardless of the care used in attempting such defeat, regardless of the techniques employed, and regardless of successful reassembly or counterfeiting of a defeated seal. Specifically, the invention of the '711 application relates to a device for visually indicating that an attempt to tamper with or defeat a locking or security seal has been made. The device is usable with seals which have a lock body, into a passageway of which the end of a male member, such as a bolt or a tip on the end of a cable, is inserted or received. Facilities in the passageway retain, and prevent removal of, the inserted male member. A frangible, brittle shroud is provided which surrounds the lock body. The material and configuration of the shroud are selected so that the application of moderate forces thereto will crack, chip or fracture it. A flange is integral with the shroud. The flange is adapted to surround the male member at its point of entry into the passageway of the lock body. The flange also will crack, chip or fracture when moderate forces are applied to it. Both the shroud and the flange will crack, chip or fracture when moderate grasping, pushing, pulling, or twisting forces are applied thereto. The flange will also crack, chip or fracture when moderate forces are applied thereto by a shim or similar object which is inserted between the flange and the male member in an attempt to insert the object into the passageway to defeat the retention and removal-preventing facilities. The cracking, chipping or fracturing of the shroud and/or the flange provide a visual indication of an attempt, successful or not, to tamper with or defeat the seal whether or not successful defeat is followed by reassembly of the seal.
Preferably, the shroud and the flange of the '711 application are unitarily molded from a frangible, brittle plastic, such as ABS or styrene. In preferred embodiments, the shroud includes a bore adopted to conformally receive the lock body. The ability of the '711 shroud/flange to provide a visual indication of tampering may be enhanced by weaking selected portions thereof, by coating the shroud/flange with a coating of a contrasting color, or by incorporating a visually distinct material into the shroud/flange.
It has been determined that sophisticated interlopers may defeat the purpose of the '711 invention. Specifically, an interloper could defeat a seal of '711 type by cutting the male member. Following this, the interloper could drive the lock body and the portion of the male member still retained therein out of the bore of the shroud. Regardless of what transpired at the site of these occurrences, the interloper would now possess an integral, undamaged shroud/flange. Subsequently, the interloper could defeat a second seal, for example by the use of a shim, and remove its male member from its lock body, which would result in the second shroud/flange becoming disintegral or otherwise possessing evidence of the seal's defeat. Thereafter, following a theft or other mischief, the interloper would discard the damaged second shroud/flange, replace it with the original integral shroud/flange and reassemble the seal.
The present invention prevents the function of the shroud/flange of '711 from being circumvented.